Use of computed tomography in the management of colorectal cancer

Figure 4 81-year-old male undergoing positron emission tomography (PET)/CT for restaging of diffuse large B cell lymphoma involving the duodenum. A: Axial non-contrast CT of the rectum showing an incidental subtle soft tissue density polypoid mass (arrow) in the right posterior lateral wall; B: This corresponded to a focal area of hypermetabolic activity (arrow), as demonstrated on fusion PET/CT. Biopsy returned as tubulovillous adenoma. This was excised. Smaller focus of increased tracer activity in keeping with normal physiologic excretion in the urine within the prostatic urethra (arrowhead).